memo = dict()
def f(k):
    global memo
    if k <= 0:
        return 0
    if k in memo:
        return memo[k]
    return 1 + (f(k-1) + f(k-2) + f(k-3) + f(k-4) + f(k-5) + f(k-6))/6

print(f(int(input())))